public class code {
    public static void main(String[] args) {
        int num = 6;
        int sz = Fac(num);
        System.out.println(sz);
    }
    public static int Fac (int num){
        if(num == 1 || num == 2){
            return 1;
        }else{
            return Fac(num - 2) + Fac(num -1);
        }
    }
}
